Fuse-case.



T. E. MURRAY.

FUSE OASE.

APPLICATION FILED M1148, 1911.

1,021,549. Patented Ma1f.26, 1912.

Orp...

THOMAS E. MURRAY, OF, vNEIN YORK, N. Y.

FUSE-CASE.

Specification of Letters Patent. Patented 1113.1'. 26, 1912.

Application led April 18, 1911. VSerial No. 621,862. y'

To all 'whom t may concern:

Be it known that I, THOMAS E. MURRAY, 4a citizen of the United States, residing at New York, in the county of New York and State of New York, have'invented a certain new and useful Improvement in F use-Cases,

of which the following is a specification.

This invention'is a novelapplication of the-principle first-embodied in the Davy safety lamp to the prevention of injury to adjacent objects due to the escape of flame from a blowing fuse. As is well known,

'flame will not pass through wire gauze or similar reti'culated metal. vI have found that this is true even of the violentand sudden outburstl of burning gas due to fuse'explosion, andthat, therefore, if such flame is intercepted by a screen 'of reticulated metal,

the danger of fire being communicated to woodwork or other ignitible material in the vicinity of the fuse is prevented.

My invention may be applied to electric fuses 1n many ways-eau, however, embodying the aforesaid principle. Thus, for example, the case which incloses the fuse strip may itself be formed of reticulated metal, or said metal may merely form a closure for an opening, or openings, in a case of other material. Some of theseways, the best I now know, areillustrated in` the accompany; ing drawings in which- Figure 1. is a perspective view showing the case formed of reticulated metal andthe securing rods attached to the exterior of the case. Fig. 2 is a4 cross sectional view of said case. Fig. 3 is a cross sectional view vof a modification in which the securing rods are attached to the inside of the tubular case, which is also provided with an inner tube or lining of paper or the like. Fig. 4 is a longitudinal section of a modification in which the case comprises two tubes of ret-icu- Vlated metal disposed one' within the other.4

Fig. 5 is, a'transverse section of said case. Fig. 6 is a longitudinal section in Vwhich the outer tubular case is of solid material with perforations and theinner t-ubular case of reticulated material.

Similar letters of reference indicate like parts.

A and B are end pieces preferably formed of single blocks of porcelain or other refrac-` tory insulating material. On each block is a contact plate C, preferably of sheet copper, bent upward to cover two sides of the large not to block and then fianged over so that its edges enter grooves D in the upper surface of the block. Another part E of each contact plate is bentupward to lie against the end -face ofthe block, and to the parts E of the to the exterior of said case on opposite sides thereof. Said rods are shouldered at J to bear against the inner faces of the/end pieces and extend through openings in said end pieces, being finally secured by bending over their extremities, as shown at K, in Figs. 1 and 4. IVithin the case and embedding the fuse is placed refractory insulating material in comminuted form, the particles of said material being sufficiently pass through the reticulations of the case.

In Fig. 3 is shown a modification, in which the rods H, I aresecured to the inside of the case, which is provided with an inner tube or lining L of paper or the like. In

this construction, the particles of the filling may be as finel as desired.

In the form shown in Figs". 4 and 5, two tubular cases "of reticulated material G, G

are exhibited, one being placed within the other, and the'supporting rods I-I, I are disposed between said cases. In this modification I have sliown no filling material, the fuse strip F being provided with a covering M of asbestos paper or similar material.

In the modification illustrated in Fig. 6, two tubular fuse cases are also employed, the outer case N being made f any suitable insulating material-preferably refractory, such as porcelain-in which are formed openings O, and the inner case G being of reticulated material. The connecting rods H, I are omitted in this figure,

Upon the explosion of the fuse, in any of the above-described forms, the fiame is screened from reaching exterior objects by the wall or closure of reticulated metal,

while the gas: pressure is relieved by escape through the interstitial spaces in said Wall or closure.

l claim:

1. An electric fuse case comprising end pieces of refractory material, a tube 0f reticulated material, and securing rods eX- tending between and engaging with said end pieces.

2. An electric fuse case comprising end piecesl of refractory material, a tube of reticulated material.l and securing rods attached to said tube, extending between and engaging with said end pieces.

3. An electric fuse case comprising two 15 tubes of reticulated metal disposed one Within the other.

In testimony whereof I have affixed my signature in presence of two witnesses.

THOMAS E. MURRAY. l-Vitnesses MAY T. MCGARRY, JN0. A.' MCKEoN. 

